/*
 GPNestedNavigationDelegate.m
 Date Created: February 19, 2010
 
 Author: Karol Krizka <kkrizka@gmail.com>
 
 Copyright (C) 2010 Green-Power
 
 URL: http://code.google.com/p/green-power
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 3 of the License, or
 (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 
 $Id$
 */

#import "GPNestedNavigationDelegate.h"


@implementation GPNestedNavigationDelegate

@synthesize topNavigationController;

// In order to display the correct navigation bar on top, we need to watch for 
// the switching of views via tabs. When a new tab is switched, we make sure that
// the new view is not a navigation controller. If it is, we display its 
// navigation bar as long as it is not showing the root view. If the view is the 
// root view, we display the main menu navigation bar, in order to provide a back
// button.
//
// One also has to make sure to set the correct title of the main navigation bar.
- (void)tabBarController:(UITabBarController *)tabBarController 
 didSelectViewController:(UIViewController *)viewController {
  UIViewController *topViewController=[[self topNavigationController] topViewController];
  
  if([viewController isKindOfClass:[UINavigationController class]]) {
    [viewController viewWillAppear:NO];
    
    UINavigationController *subNavigationController=(UINavigationController *)viewController;
    NSArray *navStack=[subNavigationController viewControllers];
    UIViewController *rootViewController=[navStack objectAtIndex:0];
        
    if([subNavigationController topViewController] == rootViewController) {
      [[self topNavigationController] setNavigationBarHidden:NO animated:NO];
      [topViewController setTitle:[rootViewController title]];
    } else {
      [[self topNavigationController] setNavigationBarHidden:YES animated:NO];
    }
  } else {
    [[self topNavigationController] setNavigationBarHidden:NO animated:NO];
    [topViewController setTitle:[viewController title]];
  }

}

- (void)navigationController:(UINavigationController *)subNavigationController
      willShowViewController:(UIViewController *)viewController
                    animated:(BOOL)animated {
  NSArray *navStack=[subNavigationController viewControllers];
  if([navStack objectAtIndex:0] == viewController) {
    [[self topNavigationController] setNavigationBarHidden:NO animated:NO];
    [subNavigationController setNavigationBarHidden:YES animated:NO]; 
  } else {
    [[self topNavigationController] setNavigationBarHidden:YES animated:NO];
    [subNavigationController setNavigationBarHidden:NO animated:NO];
  }
}
@end
